The Numbers Game: Boots, Part 2

[markojp]

I . The fitter took a look at some skiing videos of me, my stance, alignment, mobility, and strength, and basically "chose" the boot for me for 2016-17.

I hope that boot will be good this year!

Man o' man, if more people went boot shopping with a video clip of their skiing....this is helpful! I encourage everyone to do this.

 

[PTskier]

Often a too stiff boot will put a skier in the back seat.

It's not the stiffness. It is an incorrect set up for that skier. With the correct boot shaft angle, ski boot internal (zeppa) angle of the slope of the boot board, and the binding delta...heel height vs. toe height...for that skier, they will be balanced and centered with any stiffness boot. They don't have to fight to flex the boot forward to get balanced.

According to ASTM an expert skier should need 17 degrees ROM, intermediate 23, beginner 33.

That paper on the ASTM site was copyrighted in 1989. What boots would you have liked back then to be able to make the movements to ski something like K2 5500s?

the less dorsiflexion we want less net forward lean angle to open the ankle joint and permit full use of the ROM. In some instances this skier may need a stiffer flex to protect the ankle from over flexion and make more efficient use of the range of motion available.

Yep, it's all about the individual. A friend has ankles that almost do not flex. At all. He needs stiff boots to protect him from end of range pain at his very limited range of flexion, heel lifts in boots with room for the lifts, and shims under his heel bindings to get him centered and balanced. That would be horrible for just about anyone else and necessary for him.


Back to ski boot flex numbers---how do the world's skiers and ski shop owners and everyone else inspire the ski makers to institute standardized boot flex testing and labeling? I want a standard flex test is a specified flexing force for a specified distance or angle at a specified temperature. The boot & binding makers agreed on alpine boot sole and binding interface standards (ISO 5533) and release standards (ISO 9462:2014). They can do the same for boot flex. There were big safety and insurance considerations for binding interface and release standards. That isn't the same for flex, but the makers can work together for flex label standards just like they're close to being standard for sizing (and they could be a lot closer there).

 

[Viking9]

Buds statement on I think page two about the dirt bike analogy really hits home with me, that makes so much sense and so simple to me, I will definitely use that analogy.

 

[Dwight]

Bump

 

[markojp]

Back to ski boot flex numbers---how do the world's skiers and ski shop owners and everyone else inspire the ski makers to institute standardized boot flex testing and labeling? I want a standard flex test is a specified flexing force for a specified distance or angle at a specified temperature. The boot & binding makers agreed on alpine boot sole and binding interface standards (ISO 5533) and release standards (ISO 9462:2014). They can do the same for boot flex. There were big safety and insurance considerations for binding interface and release standards. That isn't the same for flex, but the makers can work together for flex label standards just like they're close to being standard for sizing (and they could be a lot closer there).

This sounds like quite a mountains from molehill problem solver. I know that I'd stay home on a warm spring day if my boots were calibrated for 15f which leads to the question... what temperature will shops need to maintain for flex compliance? And will ski areas have to issue weather/ temperature notices to skiers with sliding scales for temperature, days skied, and plastic types?

 

[scvaughn]

hyper mobile calls for limiting boot flex to prevent the skier that has the greater range from using the greater range. The boot is not a cast to put you in position, rather an early warning system to help guide you into staying in position. Hyper mobile ankle will have the skier struggling to find home base in the area of fore-aft balance. Limiting the shell flex and properly matching the pressure loading on the front of the leg, will help the early warning system to keep you in better balance. It will also help to reduce that pesky bleeding that keeps taking place on your shin, as well as those toasted quads that have you pulling off to the side of the run so you can lean on your poles and recover.

I find this relevant, given a recent boot purchase. My ankles have a much greater than average range of motion, and though I'm ~5' 10" and weigh 155 pounds, the boot fitter put me in 130s. I was skeptical at first, thinking that they would be far too stiff, but they're really not. My quads felt wasted after 4+ hours in my old "110 flex" boots, and that does not happen in the new boots. It's easier to stay balanced, in a good position.